Short course daily prednisolone therapy during an upper respiratory tract infection in children with relapsing steroid-sensitive nephrotic syndrome (PREDNOS 2):protocol for a randomised controlled trial

BACKGROUND: Relapses of childhood steroid-sensitive nephrotic syndrome (SSNS) are treated with a 4- to 8-week course of high-dose oral prednisolone, which may be associated with significant adverse effects. There is a clear association between upper respiratory tract infection (URTI) and relapse development. Previous studies in developing nations have suggested that introducing a 5- to 7-day course of daily prednisolone during an URTI may prevent a relapse developing and the need for a treatment course of high-dose prednisolone. The aim of PREDNOS 2 is to evaluate the effectiveness of a 6-day course of daily prednisolone therapy during an URTI in reducing the development of a subsequent relapse in a developed nation.METHODS/DESIGN: The subjects will be 300 children with relapsing SSNS (≥2 relapses in preceding year), who will be randomised to receive either a 6-day course of daily prednisolone or no change to their current therapy (with the use of placebo to double blind) each time they develop an URTI over 12 months. A strict definition for URTI will be used. Subjects will be reviewed at 3, 6, 9 and 12 months to capture data regarding relapse history, ongoing therapy and adverse effect profile, including behavioural problems and quality of life. A formal health economic analysis will also be performed. The primary end point of the study will be the incidence of URTI-related relapse (3 days of Albustix +++) following the first infection during the 12-month follow-up period. DNA and RNA samples will be collected to identify a potential genetic cause for the disease. Subjects will be recruited from over 100 UK centres with the assistance of the Medicines for Children Research Network. PREDNOS 2 is funded by the National Institute for Health Research Health Technology Assessment Programme (11/129/261).DISCUSSION: We propose that PREDNOS 2 will be a pivotal study that will inform the future standard of care for children with SSNS. If it is possible to reduce the disease relapse rate effectively and safely, this will reduce the morbidity and cost associated with drug treatment, notwithstanding hospital admission and parental absence from employment.TRIAL REGISTRATION: Current Controlled Trials (ISRCTN10900733).</p

Multicentre randomized controlled trial of angiotensin-converting enzyme inhibitor/angiotensin receptor blocker withdrawal in advanced renal disease:the STOP-ACEi trial

Background: Blood pressure (BP) control and reduction of urinary protein excretion using agents that block the renin–angiotensin aldosterone system are the mainstay of therapy for chronic kidney disease (CKD). Research has confirmed the benefits in mild CKD, but data on angiotensin-converting enzyme inhibitor (ACEi) or angiotensin receptor blocker (ARB) use in advanced CKD are lacking. In the STOP-ACEi trial, we aim to confirm preliminary findings which suggest that withdrawal of ACEi/ARB treatment can stabilize or even improve renal function in patients with advanced progressive CKD. Methods: The STOP-ACEi trial (trial registration: current controlled trials, ISRCTN62869767) is an investigator-led multicentre open-label, randomized controlled clinical trial of 410 participants with advanced (Stage 4 or 5) progressive CKD receiving ACEi, ARBs or both. Patients will be randomized in a 1:1 ratio to either discontinue ACEi, ARB or combination of both (experimental arm) or continue ACEi, ARB or combination of both (control arm). Patients will be followed up at 3 monthly intervals for 3 years. The primary outcome measure is eGFR at 3 years. Secondary outcome measures include the number of renal events, participant quality of life and physical functioning, hospitalization rates, BP and laboratory measures, including serum cystatin-C. Safety will be assessed to ensure that withdrawal of these treatments does not cause excess harm or increase mortality or cardiovascular events such as heart failure, myocardial infarction or stroke. Results: The rationale and trial design are presented here. The results of this trial will show whether discontinuation of ACEi/ARBs can improve or stabilize renal function in patients with advanced progressive CKD. It will show whether this simple intervention can improve laboratory and clinical outcomes, including progression to end-stage renal disease, without causing an increase in cardiovascular events

Sixteen-week versus standard eight-week prednisolone therapy for childhood nephrotic syndrome: the PREDNOS RCT.

BackgroundThe optimal corticosteroid regimen for treating the presenting episode of steroid-sensitive nephrotic syndrome (SSNS) remains uncertain. Most UK centres use an 8-week regimen, despite previous systematic reviews indicating that longer regimens reduce the risk of relapse and frequently relapsing nephrotic syndrome (FRNS).ObjectivesThe primary objective was to determine whether or not an extended 16-week course of prednisolone increases the time to first relapse. The secondary objectives were to compare the relapse rate, FRNS and steroid-dependent nephrotic syndrome (SDNS) rates, requirement for alternative immunosuppressive agents and corticosteroid-related adverse events (AEs), including adverse behaviour and costs.DesignRandomised double-blind parallel-group placebo-controlled trial, including a cost-effectiveness analysis.SettingOne hundred and twenty-five UK paediatric departments.ParticipantsTwo hundred and thirty-seven children presenting with a first episode of SSNS. Participants aged between 1 and 15 years were randomised (1 : 1) according to a minimisation algorithm to ensure balance of ethnicity (South Asian, white or other) and age (≤ 5 or ≥ 6 years).InterventionsThe control group (n = 118) received standard course (SC) prednisolone therapy: 60 mg/m2/day of prednisolone in weeks 1-4, 40 mg/m2 of prednisolone on alternate days in weeks 5-8 and matching placebo on alternate days in weeks 9-18 (total 2240 mg/m2). The intervention group (n = 119) received extended course (EC) prednisolone therapy: 60 mg/m2/day of prednisolone in weeks 1-4; started at 60 mg/m2 of prednisolone on alternate days in weeks 5-16, tapering by 10 mg/m2 every 2 weeks (total 3150 mg/m2).Main outcome measuresThe primary outcome measure was time to first relapse [Albustix® (Siemens Healthcare Limited, Frimley, UK)-positive proteinuria +++ or greater for 3 consecutive days or the presence of generalised oedema plus +++ proteinuria]. The secondary outcome measures were relapse rate, incidence of FRNS and SDNS, other immunosuppressive therapy use, rates of serious adverse events (SAEs) and AEs and the incidence of behavioural change [using Achenbach Child Behaviour Checklist (ACBC)]. A comprehensive cost-effectiveness analysis was performed. The analysis was by intention to treat. Participants were followed for a minimum of 24 months.ResultsThere was no significant difference in time to first relapse between the SC and EC groups (hazard ratio 0.87, 95% confidence interval 0.65 to 1.17; log-rank p = 0.3). There were also no differences in the incidence of FRNS (SC 50% vs. EC 53%; p = 0.7), SDNS (44% vs. 42%; p = 0.8) or requirement for other immunosuppressive therapy (56% vs. 54%; p = 0.8). The total prednisolone dose received following completion of study medication was 5475 mg vs. 6674 mg (p = 0.07). SAE rates were not significantly different (25% vs. 17%; p = 0.1) and neither were AEs, except poor behaviour (yes/no), which was less frequent with EC treatment. There were no differences in ACBC scores. EC therapy was associated with a mean increase in generic health benefit [0.0162 additional quality-adjusted life-years (QALYs)] and cost savings (£4369 vs. £2696).LimitationsStudy drug formulation may have prevented some younger children who were unable to swallow whole or crushed tablets from participating.ConclusionsThis trial has not shown any clinical benefit for EC prednisolone therapy in UK children. The cost-effectiveness analysis suggested that EC therapy may be cheaper, with the possibility of a small QALY benefit.Future workStudies investigating EC versus SC therapy in younger children and further cost-effectiveness analyses are warranted.Trial registrationCurrent Controlled Trials ISRCTN16645249 and EudraCT 2010-022489-29.FundingThis project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 23, No. 26. See the NIHR Journals Library website for further project information

Daily low-dose prednisolone to prevent relapse of steroid-sensitive nephrotic syndrome in children with an upper respiratory tract infection:PREDNOS2 RCT

BACKGROUND: Most children with steroid-sensitive nephrotic syndrome have relapses that are triggered by upper respiratory tract infections. Four small trials, mostly in children already taking maintenance corticosteroid in countries of different upper respiratory tract infection epidemiology, showed that giving daily low-dose prednisone/prednisolone for 5-7 days during an upper respiratory tract infection reduces the risk of relapse. OBJECTIVES: To determine if these findings were replicated in a large UK population of children with relapsing steroid-sensitive nephrotic syndrome on different background medication or none. DESIGN: A randomised double-blind placebo-controlled trial, including a cost-effectiveness analysis. SETTING: A total of 122 UK paediatric departments, of which 91 recruited patients. PARTICIPANTS: A total of 365 children with relapsing steroid-sensitive nephrotic syndrome (mean age 7.6 ± 3.5 years) were randomised (1 : 1) according to a minimisation algorithm based on background treatment. Eighty children completed 12 months of follow-up without an upper respiratory tract infection. Thirty-two children were withdrawn from the trial (14 prior to an upper respiratory tract infection), leaving a modified intention-to-treat analysis population of 271 children (134 and 137 children in the prednisolone and placebo arms, respectively). INTERVENTIONS: At the start of an upper respiratory tract infection, children received 6 days of prednisolone (15 mg/m2) or an equivalent dose of placebo. MAIN OUTCOME MEASURES: The primary outcome was the incidence of first upper respiratory tract infection-related relapse following any upper respiratory tract infection over 12 months. The secondary outcomes were the overall rate of relapse, changes in background treatment, cumulative dose of prednisolone, rates of serious adverse events, incidence of corticosteroid adverse effects, change in Achenbach Child Behaviour Checklist score and quality of life. Analysis was by intention-to-treat principle. The cost-effectiveness analysis used trial data and a decision-analytic model to estimate quality-adjusted life-years and costs at 1 year, which were then extrapolated over 16 years. RESULTS: There were 384 upper respiratory tract infections and 82 upper respiratory tract infection-related relapses in the prednisolone arm, and 407 upper respiratory tract infections and 82 upper respiratory tract infection-related relapses in the placebo arm. The number of patients experiencing an upper respiratory tract infection-related relapse was 56 (42.7%) and 58 (44.3%) in the prednisolone and placebo arms, respectively (adjusted risk difference -0.024, 95% confidence interval -0.14 to 0.09; p = 0.70). There was no evidence that the treatment effect differed when data were analysed according to background treatment. There were no significant differences in secondary outcomes between treatment arms. Giving daily prednisolone at the time of an upper respiratory tract infection was associated with increased quality-adjusted life-years (0.9427 vs. 0.9424) and decreased average costs (£252 vs. £254), when compared with standard care. The cost saving was driven by background therapy and hospitalisations after relapse. The finding was robust to sensitivity analysis. LIMITATIONS: A larger number of children than expected did not have an upper respiratory tract infection and the sample size attrition rate was adjusted accordingly during the trial. CONCLUSIONS: The clinical analysis indicated that giving 6 days of daily low-dose prednisolone at the time of an upper respiratory tract infection does not reduce the risk of relapse of steroid-sensitive nephrotic syndrome in UK children. However, there was an economic benefit from costs associated with background therapy and relapse, and the health-related quality-of-life impact of having a relapse. FUTURE WORK: Further work is needed to investigate the clinical and health economic impact of relapses, interethnic differences in treatment response, the effect of different corticosteroid regimens in treating relapses, and the pathogenesis of individual viral infections and their effect on steroid-sensitive nephrotic syndrome. TRIAL REGISTRATION: Current Controlled Trials ISRCTN10900733 and EudraCT 2012-003476-39. FUNDING: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 26, No. 3. See the NIHR Journals Library website for further project information

Maternal exposure to polychlorinated biphenyls and the secondary sex ratio: an occupational cohort study

Though commercial production of polychlorinated biphenyls was banned in the United States in 1977, exposure continues due to their environmental persistence. Several studies have examined the association between environmental polychlorinated biphenyl exposure and modulations of the secondary sex ratio, with conflicting results. Our objective was to evaluate the association between maternal preconceptional occupational polychlorinated biphenyl exposure and the secondary sex ratio. We examined primipara singleton births of 2595 women, who worked in three capacitor plants at least one year during the period polychlorinated biphenyls were used. Cumulative estimated maternal occupational polychlorinated biphenyl exposure at the time of the infant's conception was calculated from plant-specific job-exposure matrices. A logistic regression analysis was used to evaluate the association between maternal polychlorinated biphenyl exposure and male sex at birth (yes/no). Maternal body mass index at age 20, smoking status, and race did not vary between those occupationally exposed and those unexposed before the child's conception. Polychlorinated biphenyl-exposed mothers were, however, more likely to have used oral contraceptives and to have been older at the birth of their first child than non-occupationally exposed women. Among 1506 infants liveborn to polychlorinated biphenyl-exposed primiparous women, 49.8% were male; compared to 49.9% among those not exposed (n = 1089). Multivariate analyses controlling for mother's age and year of birth found no significant association between the odds of a male birth and mother's cumulative estimated polychlorinated biphenyl exposure to time of conception. Based on these data, we find no evidence of altered sex ratio among children born to primiparous polychlorinated biphenyl-exposed female workers

Accuracy of glomerular filtration rate estimation using creatinine and cystatin C for identifying and monitoring moderate chronic kidney disease: the eGFR-C study

Background Estimation of glomerular filtration rate using equations based on creatinine is widely used to manage chronic kidney disease. In the UK, the Chronic Kidney Disease Epidemiology Collaboration creatinine equation is recommended. Other published equations using cystatin C, an alternative marker of kidney function, have not gained widespread clinical acceptance. Given higher cost of cystatin C, its clinical utility should be validated before widespread introduction into the NHS. Objectives Primary objectives were to: (1) compare accuracy of glomerular filtration rate equations at baseline and longitudinally in people with stage 3 chronic kidney disease, and test whether accuracy is affected by ethnicity, diabetes, albuminuria and other characteristics; (2) establish the reference change value for significant glomerular filtration rate changes; (3) model disease progression; and (4) explore comparative cost-effectiveness of kidney disease monitoring strategies. Design A longitudinal, prospective study was designed to: (1) assess accuracy of glomerular filtration rate equations at baseline (n = 1167) and their ability to detect change over 3 years (n = 875); (2) model disease progression predictors in 278 individuals who received additional measurements; (3) quantify glomerular filtration rate variability components (n = 20); and (4) develop a measurement model analysis to compare different monitoring strategy costs (n = 875). Setting Primary, secondary and tertiary care. Participants Adults (≥ 18 years) with stage 3 chronic kidney disease. Interventions Estimated glomerular filtration rate using the Chronic Kidney Disease Epidemiology Collaboration and Modification of Diet in Renal Disease equations. Main outcome measures Measured glomerular filtration rate was the reference against which estimating equations were compared with accuracy being expressed as P30 (percentage of values within 30% of reference) and progression (variously defined) studied as sensitivity/specificity. A regression model of disease progression was developed and differences for risk factors estimated. Biological variation components were measured and the reference change value calculated. Comparative costs of monitoring with different estimating equations modelled over 10 years were calculated. Results Accuracy (P30) of all equations was ≥ 89.5%: the combined creatinine–cystatin equation (94.9%) was superior (p &lt; 0.001) to other equations. Within each equation, no differences in P30 were seen across categories of age, gender, diabetes, albuminuria, body mass index, kidney function level and ethnicity. All equations showed poor (&lt; 63%) sensitivity for detecting patients showing kidney function decline crossing clinically significant thresholds (e.g. a 25% decline in function). Consequently, the additional cost of monitoring kidney function annually using a cystatin C-based equation could not be justified (incremental cost per patient over 10 years = £43.32). Modelling data showed association between higher albuminuria and faster decline in measured and creatinine-estimated glomerular filtration rate. Reference change values for measured glomerular filtration rate (%, positive/negative) were 21.5/−17.7, with lower reference change values for estimated glomerular filtration rate. Limitations Recruitment of people from South Asian and African-Caribbean backgrounds was below the study target. Future work Prospective studies of the value of cystatin C as a risk marker in chronic kidney disease should be undertaken. Conclusions Inclusion of cystatin C in glomerular filtration rate-estimating equations marginally improved accuracy but not detection of disease progression. Our data do not support cystatin C use for monitoring of glomerular filtration rate in stage 3 chronic kidney disease

Can we achieve better trial recruitment by presenting patient information through multimedia? : Meta-analysis of 'studies within a trial' (SWATs)

Acknowledgements We would like to acknowledge all those in the trial teams who supported this programme of SWATs, as well as our public contributors (Ailsa Donnelly and Judith Hogg). We also thank Paul Wallace (original MRC START applicant) and Reason Digital for multimedia development. We thank the patients who participated in the GHT2000, PSM COPD, HI-Light, seAFOod and STOP-ACEi trials, the members of the Birmingham and Nottingham Clinical Trials Units, the Research and Development Team at Hull University Teaching Hospitals NHS Trust, and the staff members at all the participating trial centres. Funding The authors wish to acknowledge the MRC Methodology Research Programme which funds this research (MRC grant reference: G1002325). The MRC has no role in study design; collection, management, analysis and interpretation of data; writing of the report; or the decision to submit the report for publication.Peer reviewedPublisher PD

Efficacy and safety of eculizumab in children with Shiga-toxin-producing Escherichia coli haemolytic uraemic syndrome: the ECUSTEC RCT

Background Shiga-toxin-producing Escherichia coli haemolytic uraemic syndrome affects ~100 United Kingdom children each year. Around half need dialysis, a quarter develop serious complications with long-term consequences and ~3% die. No effective intervention is known; however, some studies report eculizumab, effective in atypical haemolytic uraemic syndrome, may be effective. Objectives To determine whether the severity of Shiga-toxin-producing Escherichia coli haemolytic uraemic syndrome is less in those given eculizumab. Design Randomised, double-blind, placebo-controlled, parallel-group trial with internal pilot phase and nested mechanistic laboratory studies. Setting Paediatric nephrology units in 12 United Kingdom hospitals. Participants Children aged 6 months to < 19 years weighing ≥ 5 kg, with presumed Shiga-toxin-producing Escherichia coli haemolytic uraemic syndrome, including ‘injury’ or ‘failure’ category of the acute kidney injury paediatric risk/injury/failure/loss/end criteria. Intervention Participants were randomised in a 1 : 1 ratio to receive intravenous eculizumab or placebo on day 1 and 8. All received meningococcal vaccination and prophylactic antibiotics. Main outcome measures The primary outcome measure was a multidomain clinical severity score, reflecting morbidity until day 60. Secondary outcome measures included survival, duration of renal replacement therapy, persistent neurological defect (day 60) and presence of chronic kidney disease at 1 year. Mechanistic studies assessed complement activation and vascular endothelial growth factor profiles in plasma ± urine samples. In vitro cell co-culture work assessed the effect of Shiga toxin on endothelial cells. Results Thirty-six participants from 10 sites were randomised: 17 to eculizumab and 19 to placebo. The target sample size was 134 participants – recruitment stopped early due to low recruitment (factors included reduced incidence and limited out-of-hours research infrastructure) and the COVID-19 pandemic. The mean clinical severity score for participants randomised to eculizumab was 11.5 (standard deviation 8.4) compared to 14.6 (standard deviation 7.7) for participants randomised to placebo (adjusted mean difference: −2.5, 95% confidence interval −7.8 to 2.8, p = 0.3). Five participants (three eculizumab, two placebo) experienced an adverse event; there were seven serious adverse events in six participants (five eculizumab, one placebo). Urinary complement factor H and vascular endothelial growth factor levels were high initially and subsequently normalised. Shiga toxin caused a podocyte-dependent decrease in endothelial cell factor H levels. Conclusions and limitations There was no significant difference in mean clinical severity score between eculizumab and placebo groups – since the trial was underpowered, this cannot be interpreted as evidence of no effect. No significant safety concerns were observed. With further validation, the Eculizumab in Shiga-toxin-producing Escherichia coli Haemolytic Uraemic Syndrome clinical severity score may be an outcome measure for future trials. Our results imply that Shiga toxin causes complement-dependent glomerular endothelial cell injury through its action on podocytes and subsequent cellular cross-talk. Future work We will continue to investigate cross talk between podocytes and endothelial cells after exposure to Shiga toxin and further develop plasma/urine biomarkers for diagnosis of Shiga-toxin-producing Escherichia coli haemolytic uraemic syndrome. Trial registration This trial is registered as EudraCT-2016-000997-39 and ISRCTN89553116. Funding This award was funded by the National Institute for Health and Care Research (NIHR) Efficacy and Mechanism Evaluation (EME) programme (NIHR award ref: 14/48/43) and is published in full in Efficacy and Mechanism Evaluation; Vol. 11, No. 11. See the NIHR Funding and Awards website for further award information. Plain language summary Why did we do this study? Annually, approximately 100 United Kingdom children develop Shiga-toxin-producing Escherichia coli haemolytic uraemic syndrome after infection with a diarrhoea-causing bug. The bug makes a toxin (Shiga toxin) that damages blood vessels, especially in the kidneys. Half need dialysis (artificial kidney support), about a quarter suffer fits or a stroke and about 3% die. Most children fully recover, but about a quarter suffer permanent kidney or brain damage. There are no known effective treatments. Eculizumab, a medicine which blocks part of the immune system called complement, may work. What was the question? Does eculizumab reduce the severity of Shiga-toxin-producing Escherichia coli haemolytic uraemic syndrome? What did we do? We planned to recruit 134 children, but difficulties with recruitment and the COVID-19 pandemic meant the study was stopped early after 36 children had been recruited; 17 received eculizumab, 19 received a dummy medicine (placebo). We compared children in each group using a score that measured how their kidneys and other organs were affected. We studied samples of their blood and urine, and also how Shiga toxin damages kidney cells in the laboratory. What did we find? The severity of illness was similar in both groups; however, because we only studied a small number of children, we cannot be sure this means that eculizumab does not work. Eculizumab appeared to be safe in this condition. In the blood and urine samples, we saw evidence that complement is involved in the illness. We also discovered a new way that Shiga toxin damages kidney cells. What does this mean? We have been unable to show whether eculizumab is a worthwhile treatment for children with this condition. However, we have learnt lots about how the illness is caused and hope these results can be combined with other studies to give us a clearer answer. Scientific summary Background Shiga-toxin-producing Escherichia coli haemolytic uraemic syndrome affects around 100 UK children each year, following gastrointestinal infection with Shiga-toxin-producing E. coli. Around half of affected children will need dialysis, about a quarter develop serious complications with long-term consequences and about 3% die. All patients require long-term follow-up because of the risk of developing chronic kidney disease (CKD). No intervention has definitively been shown to reduce morbidity or mortality in this condition, and therefore treatment is supportive. Case reports and case series suggest that eculizumab (Soliris®, Alexion Pharmaceuticals, Boston, MA), an inhibitor of the complement system and an effective treatment for the related condition, atypical haemolytic uraemic syndrome, may be effective in this condition. Until very recently, there were no published data regarding the efficacy and safety of eculizumab in Shiga-toxin-producing E. coli haemolytic uraemic syndrome, and yet despite this its use has risen globally. A recent randomised phase 3 clinical trial reported comparison of eculizumab with placebo in 100 children with Shiga-toxin-producing E. coli haemolytic uraemic syndrome (Garnier A, Brochard K, Kwon T, Sellier-Leclerc A-L, Lahoche A, Allain Launay E, et al. Efficacy and safety of Eculizumab in pediatric patients affected by Shiga Toxin-Related Hemolytic and Uremic Syndrome: a randomized, placebo-controlled trial. J Am Soc Nephrol 2023;34:1561–73). Patients with severe multi-organ involvement were excluded. Four patients in the placebo group were withdrawn and subsequently received eculizumab. There was no difference between treatment groups in the proportion of children who required renal replacement therapy 48 hours after randomisation, In addition, no differences between groups were seen in the secondary outcome measures of extra-renal manifestations, duration of hospitalisation and mortality. During follow up, there was a slight difference in the proportion who exhibited renal sequelae at 12 months post randomisation (20 patients in the eculizumab group (43.48%) and 29 patients (64.44%) in the placebo group (P = 0.04). The authors concluded that eculizumab seemed to have no impact on the course of acute kidney injury and interpreted the 12-month follow-up data with caution. No data have been published which include the role of eculizumab in patients with severe manifestations of disease in a controlled setting. Objectives of the main trial The Eculizumab in Shiga-toxin-producing Escherichia coli Haemolytic Uraemic Syndrome (ECUSTEC) trial was designed to test the hypothesis that treatment with eculizumab reduces the severity of Shiga-toxin-producing E. coli haemolytic uraemic syndrome in children aged 6 months– 150 × 109/l). Duration of haemolysis (number of days until lactate dehydrogenase within local centre reference range). Number of packed red blood cell transfusions required and volume (ml/kg). Duration markers of inflammation present (number of days until neutrophil cell count and C-reactive protein are in normal range for that centre). Persistent neurological defect at day 60 measured by structured expert assessment to include central nervous system examination, vision, hearing and neuropsychological assessment. CKD at 52 weeks (a composite end point of the presence of hypertension, albuminuria or estimated glomerular filtration rate (eGFR) < 90 ml/minute/1.73 m2 at 52 weeks). eGFR measurement using a centralised cystatin C assay at 52 weeks. Mechanistic studies Urine CFH levels. Urine VEGF levels. Presence of urine markers of podocyte damage (nephrin and Wilms tumour-1). Plasma VEGF and factor H levels. Plasma complement activation products (Bb, C3a, C4a and sC5b9 by ELISA and C3 and C4 activation markers by degradomics). Glomerular endothelial surface levels of factor H and C3d (a marker of complement activation) in a co-culture models of human conditionally immortalised podocytes and glomerular endothelial cells exposed to Shiga toxin. Whole exome sequencing and serum anti-factor H antibody levels. Results The target sample size was 134 participants, but recruitment was stopped early due to low recruitment and the impact of the COVID-19 pandemic. At the point the trial was stopped, 108 children had been screened for participation, of whom 87 were deemed eligible to participate. Thirty-six children were consented and randomised; 17 were randomised to eculizumab and 19 were randomised to placebo. One participant withdrew from the trial and one participant died. The majority of baseline data of the participants were comparable across the two groups; however, the participants in the placebo group were slightly older and consequently heavier than those in the eculizumab group. Reasons for slow recruitment included a fall in the incidence of Shiga-toxin-producing E. coli haemolytic uraemic syndrome during the trial period (up to a 37% reduction) and a lack of out-of-hours infrastructure for undertaking acute interventional clinical trials in children. The mean CSS at day 60 for participants randomised to eculizumab was 11.5 [standard deviation (SD) 8.4] compared to 14.6 (SD 7.7) for participants randomised to placebo [adjusted mean difference: −2.5, 95% confidence interval (CI) −7.8 to 2.8, p = 0.3]. Five participants (three eculizumab, two placebo) experienced an adverse event, and there were seven serious adverse events (SAEs) in six participants (five eculizumab, one placebo). None of the SAEs were considered related to the trial treatment. Mechanistic substudies Of the 36 participants recruited to the main trial, 32 consented to take part in the mechanistic studies and provided blood and/or urine samples. In anuric patients, only blood samples were collected. Urine factor H and vascular endothelial growth factor levels in serial samples The highest urine factor H levels were at day 1 (150 ng/ml), diminishing by day 4 (30 ng/ml), and completely normalising by day 30 (undetectable). The highest urine VEGF levels were at day 1 (average 1300 ng/ml) and by day 30 the levels were below 20 ng/ml. Markers of podocyte damage Western blots of urine cell pellets showed acute podocyte loss during active disease, which recovered by day 8. Plasma factor H and vascular endothelial growth factor levels No difference was seen for plasma levels of either factor H or VEGF at day 1 or day 30. Plasma degradomics analysis In a sample of five patients, N-termini consistent with complement C3 and C4 activation were much more abundant at day 1 compared with day 3. In vitro cell co-culture In response to Shiga toxin, there was a reduction in glomerular endothelial factor H levels, accompanied by evidence of complement activation (increased C3d levels) and this was critically dependent on the presence of podocytes. Shiga toxin had no effect when added to endothelial cells alone. Plasma complement activation products Mean plasma levels of Bb were elevated in both groups at baseline (4.38 mcg/ml in the eculizumab group and 10.38 mcg/ml in the placebo group, normal range 0.48–1.62 mcg/ml). They were also elevated at day 2 (5.91 mcg/ml in the eculizumab group and 4.09 mcg/ml in the placebo group) and day 4 (4.90 mcg/ml in the eculizumab group and 3.16 mcg/ml in the placebo group). At day 6 and day 8, Bb levels remained elevated in the placebo group (6.21 and 3.47 mcg/ml respectively) but were normal in the eculizumab group. In both groups, mean Bb levels were in the normal range at day 30. Mean plasma levels of C3a were elevated in both groups at baseline and at days 2 and 4. At days 6 and 8, mean levels remained elevated in the placebo group while mean levels in the eculizumab group were in the normal range. Levels were in the normal range for both groups by day 30. Mean plasma levels of C4a were elevated at all time points in both groups but fell significantly at day 30. Mean levels were 3852, 3026, 3423, 3067, 3425 and 1623 ng/ml at days 1, 2, 4, 6, 8 and 30 in the eculizumab group (normal range 110–699 ng/ml) and 3970, 3573, 2673, 4348, 2844 and 1992 ng/ml at the same respective time points in the placebo group. Mean plasma levels of sC5b9 were normal in both groups at all time points with the exception of day 4 and day 6 in the placebo group, which were elevated (487 and 514 ng/ml respectively, normal range 95–467 ng/ml). In the placebo group, a linear relationship was not established between CSS and baseline Bb (r = 0.43, p = 0.2); C3a (r = −0.16, p = 0.7); C4a (r = 0.15, p = 0.7) or sC5b9 (r = −0.17, p = 0.7). Similarly, a linear relationship was not established between CSS and the maximum value of Bb (r = 0.45, p = 0.1); C3a (r = 0.15, p = 0.6); C4a (r = 0.23, p = 0.4) or sC5b9 (r = −0.22, p = 0.5). Delivery of Shiga toxin to podocytes from patient-derived neutrophils Insufficient patient samples were obtained to complete this part of the work. Genetic variations in patients with Shiga-toxin-producing Escherichia coli haemolytic uraemic syndrome Data from whole exome sequencing have been obtained and analysis is ongoing. Conclusions In children with Shiga-toxin-producing E. coli haemolytic uraemic syndrome, the mean CSSs at day 60 were similar between those randomised to eculizumab and those randomised to placebo. However, since the trial was stopped early and did not recruit to the planned sample size, this cannot be interpreted as evidence of no effect. In order to deliver successful clinical trials of investigational medicinal products in acutely unwell children, a review of out-of-hours paediatric research infrastructure may be required. In the mechanistic substudies, we have established that urine factor H and VEGF levels are sensitive measures of early disease activity, and have demonstrated complement activation in patient serum using both ELISA and sophisticated proteomics technology. Urine factor H and VEGF levels and plasma degradomics for C3 and C4 proteins could all be further explored as new biomarkers of acute Shiga-toxin-producing E. coli haemolytic uraemic syndrome. Our co-culture cell work has demonstrated that podocyte cross-talk is responsible for factor H and complement activation levels on endothelial cells. Collectively this strongly supports the mechanistic hypothesis of a complement-mediated disease driven via the podocyte as the target cell. Trial registration This trial is registered as EudraCT2016-000997-39 and ISRCTN89553116. Funding This award was funded by the National Institute for Health and Care Research (NIHR) Efficacy and Mechanism Evaluation (EME) programme (NIHR award ref: 14/48/43) and is published in full in Efficacy and Mechanis